Apparatus for incorporating fluids into liquids



Aug. 15, 1961 R. G. L. AUDRAN 2,995,287

APP'EUS WK INIW'JTHW W0 LIQUIDS Filed July 5, 195? 3 2 Sheets-Sheet 1 ROGER GASTON LOUIS AUDRAN HVVENIUR.

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Aug. 15, 1961 R. G. AUDRAN APPARATUS FOR INCORPORATING FLUIDS INTO LIQUIDS 2 Sheets-Sheet 2 Filed July 5, 1957 IN VENTOR.

ROGER GASTON LOUIS AUDRAN r W EI.

ATTORNEYS Unite This invention relates to a rotating nozzle mixer of the revolving cone type in which a liquid in divided form is dispersed into another, which device consists of two faced cones rotating upon a hollow shaft by means of which a liquid in divided form is fed through the hollow shaft into the space between the cones and into a mass of other liquid. 7

Usually in the mixing of liquids the two or more masses of liquids to be mixed are added to the same vessel and are subjected to agitation to disperse one or more of the liquids into the other. This method has been effective in the preparation of certain mixtures but in those cases where it is desired to disperse a liquid in a very finely divided state into a mass of other liquid some other means must ordinarily be employed. For example, in the formation of oil-in-water emulsions or in the carrying out of chemical reactions where a finely divided precipitate is desired, at least one of the liquids should preferably be in finely divided condition when dispersed in the other liquid or liquids. The devices which will accomplish this result appear to be limited.

A common type of revolving cone mixer comprises one or more hollow truncated cones which rotate axially. In a current model of a mixer of this type the cones are open at the ends and are fitted with vanes on the inside surface thereof to agitate the material being mixed. These mixers are ill adapted to the incorporation of a liquid in dissipated form into the mass of a second liquid.

One object of my invention is to provide a rotating nozzle mixer of the revolving cone type which is adapted to rapidly disperse at least one fluid or liquid into a mass of another liquid. Another object of my invention is to provide a procedure for mixing liquids, or a fluid with a liquid, for the carrying out of a chemical reaction in which there is substantially total suppression of any local excess of one of the reagents in the carrying out of that reaction. A further object of my invention is to provide a procedure wherein the miscibility of a dispersed phase is increased due to the liquid which goes to make up that phase being introduced into another liquid in dissipated condition. A still further object of my invention is to provide a procedure for carrying out a reaction involving two or more liquids in which the reaction speed is markedly increased due to rapid contact of the reactants involved. A still further object of my invention is to provide a procedure wherein the heat of reaction is distributed quickly throughout an entire mass of the bulk liquid which is being employed for the reaction. Other objects of my invention will appear herein.

I have found that these and other objects are realized by means of a rotating nozzle mixer of the revolving cone type which comprises two coaxial cones with their bases facing each other and having a limited clearance therebetween which cones are attached to and rotated by a hollow shaft which shaft is provided with apertures leading into the space between the two cones whereby particles of a fiuid introduced into that space from the hollow shaft may be rapidly dispersed throughout the bulk liquid in which the cones are rotated. I have found that by means of this device suspensions or dispersions of one liquid in another are readily prepared such as for example oil-in-water emulsions. I have found that by tes Patent "ice carrying out reactions in which two liquids react to form a precipitate the product obtained may be prepared in finely divided form by the use of my device.

According to the invention the dispersion of a fluid in a very finely divided state in a liquid mass is effected according to a method characterized by the fact that the fluid is directed toward lamellar suction zones created in the midst of the liquid mass and when the fluid is subjected to the suction prevailing in said zone the fluid undergoes such a lamellar drawing out that it enters into the liquid mass in the form of a sheet with a large specific surface area. The lamellar drawing out of the fluid when it is subjected to the suction prevailing in said zone, appears to be due to a centrifugal force applied to said fluid and to which said suction is added or it may be due only to said suction.

The thus defined method makes it possible to disperse a liquid or a gas quickly in a liquid mass, to mix two liquid reagents while eliminating practically completely any local excess of one of the reagents, to increase the speed of dissolving a dispersed phase as a result of its being introduced in a very finely divided state into a liquid dispersion medium and to dissipate any heat of reaction which makes possible increasing the speed at which a reaction may be carried out.

The above as well as further advantages of the present invention will be more completely understood from the following description thereof, reference being made to the accompanying drawing wherein:

FIG. 1 is a side elevation of a rotating nozzle mixing apparatus in accordance with my invention;

FIG. 2 is a sectional view of the distributing portion of that apparatus;

FIG. 3 is a transverse sectional view taken on line 3-3 of FIG. 2;

FIG. 4 is a sectional view of a modification of the distributing portion of my mixing apparatus shown in FIG. 2;

FIG. 5 is a sectional view of a distributor portion of my mixing apparatus provided with baifles;

FIG. 6 is a side elevation of a modification of a mixing apparatus in accordance with my invention which is adapted to the introduction of a plurality of liquids in finely divided form into a mass of liquid;

FIG. 7 is a sectional view of an agitator portion of a mixing apparatus in accordance with my invention adapted to the introduction of a plurality of liquids in dispersed form into a liquid mass;

FIG. 8 is a transverse sectional view taken on line 8-8 of FIG. 7.

FIG. 1 of the drawing illustrates a combination of apparatus which is effective to prepare fluid-in-fiuid mixtures as described herein. A hollow shaft 1 contains on the terminal portions thereof two coaxial cones arranged in faced relationship, the top cone 2 being preferably recessed and the bottom cone 3 being unrecessed. The bottom cone 3 is attached to the terminal portion of the shaft to which it may be permanently joined or it may be joined by means of screw threads. The upper recessed cone 2 is conveniently attached to the shaft in threaded relationship thereto and after the spacing between the two cones has been adjusted as desired, the cone 2 may then be fastened in place such as by means of lock nut 6. If desired, the upper cone may be permanently attached to the shaft and the lower cone 3 and the bottom of the hollow shaft may be threaded so that the space between the cones can be adjusted by rotation of cone 3 either clockwise or counterclockwise. In the arrangement shown the lower cone has a shallow collar with holes to line up with the holes of the shaft if the arrangement of FIG. 2 is employed.

FIG. 2 shows in section an agitating portion of a mixing apparatus illustrated in FIG. 1. FIG. 2 shows that the threaded collar of cone 2 may be adjusted upon the threaded portion of the hollow shaft to obtain the desired spacing between the cones of the mixer. This cone ,2 is then locked in place by means of lock nut 6. The hollow shaft is provided with apertures opening into the inner recess of the mixer whereby liquid is fed therein and from which the liquid is distributed outwards upon rotation of the mixer. This structure is shown in more detail in FIG. 3 indicating four holes in the hollow shaft which line up with corresponding holes in the collar of .cone 3. The number of holes to be used or their distribution in the hollow shaft is a matter of choice by the individual operator. The hollow shaft 1 to which the cones are attached may be rotated by any suitable means. This shaft in the drawing is held by holder 8 provided with a bearing within which the shaft rotates and a pulley wheel 9 by which the shaft is rotated motivated by a belt and motor not shown.

When the fluid that is to be introduced into the liquid mass is a liquid, it is desirable that the hollow shaft 1 be provided with a centrifugal trap 7, that connects with the hollow space inside of the shaft and assures the connection between the upper part and the lower part of the shaft which are separated by a solid division. If desired, two or more similar traps may be provided at this point. The length of the branches of the trap must be suflicient to balance the reduced pressure that is created at the selected speed of rotation. In the absence of such .a trap or an equivalent arrangement air would be sucked into the hollow shaft with the liquid. If the presence of air bubbles in the liquid passed through the hollow shaft is not considered objectionable or if a gaseous liquid is employed, the trap may be dispensed with.

Liquid may be fed into the hollow shaft of the mixer by means of nonrotating tube 10. The rotation of the cones of the mixer provides suction which together with the force of gravity propels the liquid through the hollow shaft which liquid is eventually discharged through the holes into the interior recess of the revolving cones from which it is rapidly dissipated into the mass of liquid in which those cones are rotating. If desired, the upper cone 2 may be provided on its inside surface with concentric grooves as in some cases it is thought that the presence of these grooves contributes to the uniformity of the fluid over the interior surface of this cone.

The clearance between the lips of the cones may be varied and may depend on the rate at which the liquid is passed through the hollow shaft. For instance, if an aqueous liquid having a viscosity approaching that of water is flowed through the shaft at a rate of approximately 50 cc. per minute the clearance between the cones may be approximately inch. With a more rapid flow of liquid a greater clearance would be desirable while if the liquid is introduced more slowly the clearance might be less such as ,4 inch. The cones may be rotated at the speed desired, ordinarily at least 1,000 rpm. In most operations some convenient speed within the range of 2,000-10 000 r.p.m. accomplishes the desired effect without introducing undesirable factors in the mixing operation.

FIG. 4 is a sectional view of a modification of the distributor portion of a mixing apparatus in accordance with my invention. This modification differs from that illustrated in FIG. 2 in that the holes 4 are located nearer the apex of the top cone whereas in FIG. 2 the holes are nearer the base of that cone. The upper cone in FIG. 4 is illustrated as provided with concentric grooves 11 on the interior surface thereof which in some cases may be desirable to assist in the distribution of the fluid over that surface.

FIG. 5 is a sectional view of a modification of the distributing portion of the apparatus, the rotating nozzle portion being similar to that shown in FIG. 4. However, this distributing portion is provided with ,a partial enclosure composed of upper cover *14 and lower cover 15 which covers are provided with baffle plates 12 and 13 arranged therein to contribute to the mixing operation. These baffle plates or blades may be attached to the cones in any suitable manner and are directed or curved in a suitable manner to assure a radial or .almost radial flow of the currents of liquid upon leaving the blades under the conditions of operation of the device. The covers or conical flanges 14 and 15 have central inlets 16 and 17 respectively. The angle of the vertex of an extension of the conical flange is, in the method of embodiment shown, smaller than the angle of the vertex of the cones so that each flange, in conjunction with the external surface of the cone to which it is attached, defines a Venturi tube, which accelerates the flow of the liquid upon leaving the blades and increases the efficiency of the devices. However, the angles at the vertex of the conical flanges could be equal to that of the cones. In using this mixing device in the preparation of precipitates by chemical reaction such as in the preparation of photographic emulsions, it is preferable to carry out the reaction in a baifled container to break up the flow action.

FIG. 6 is a view in section of a modified mixing apparatus in accordance with my invention. In this apparatus there are three distributing devices of the revolving cone type designated B into each of which fluids are separately introduced by means of concentric tubes making up the shaft which rotates the agitating device. This apparatus is also provided with baflles designated C exterior the distributing cones the employment of which is optional with the individual operator. By means of this apparatus a plurality of fluids may be introduced into a bulk liquid while those fluids are in a finely dispersedcondition which would be desirable where several liquids are mixed together in the carrying out of a chemical reaction to prepare a finely divided precipitate.

FIG. 7 is a sectional view of a modification of a distributing portion of a mixing apparatus provided with hollow rings 21 on the inside of the upper cone each ring being entered from the shaft by a hole 20 to introduce a different fluid than is provided into each other ring. In this device the shaft used is composed of a tube having therein three adjacent tubes so as to supply fluids separately as shown.

FIG. 8 is a transverse sectional view taken on line 8-8 of FIG. 7 which illustrates the composition of the shaft which is employed to rotate the agitating device of FIG. 7. This shaft has therein 3 adjacent tubes 31, 32' and 33 to supply fluids to the rings 21 of the distributor. By this agitating device a plurality of fluids may be introduced into a bulk liquid in the mixing operation. The

inner surface of the upper cone may or may not be provided with concentric grooves as desired.

The diameter of the bases of the cones of rotating nozzle mixers in accordance with my invention may be any length desired. It has been found that for laboratory size operation, cones of two-inch diameter perform admirably. For use in larger size tanks greater diameters such as up to 8 inches or more depending on the size of operation may be used allowing more rapid introduction of liquid due to the larger circumference which is dispersing that liquid into the mass in which the cones rotate. Although the altitude of the cone is not critical, we have found that the more nearly disk-shaped the cones become the more convenient their operation. For instance, the angle at the vertex of the cone is desirably obtuse, an angle between about and being very suitable. Although in the illustrated methods of embodiment a rotary movement is imparted to the shaft and in turn the cones thus assuring a centrifugal effect on the fluids in contact with the outside surfaces and possibly the inside surfaces of the cones, a vibrator may be employed which transmits a periodic axial alternating movement to the hollow shaft l, at a frequency which may be for example between 25. and 1.00 or more.

In the use of the mixing apparatus in accordance with my invention, the distributing portion of the apparatus is immersed in a body of liquid in a container into which the other fluid or fluids are to be introduced. If an oil-inwater emulsion is to be prepared the body of liquid may be water containing for instance a small amount of a wetting agent such as sodium lauryl sulfate, soap or oleoyl methyl taurine. The oil such as a petroleum distillate, a vegetable oil or a dye in an oil vehicle is introduced through the shaft into the distributor and from there is dispersed into the body of liquid in which the agitating is occurring. If a precipitate is desired such as in the preparation of a silver halide photographic emulsion the agitating device may be introduced into a body of water containing gelatin in solution therein and silver nitrate and alkali metal halide may be introduced therein by separate rotating nozzle distributors either on individual shafts or on a single shaft having multiple conduits or one of the reagents such as the alkali metal halide or ammoniacal silver nitrate may be present in the gelatin solution and the other liquid introduced through the shaft of the mixing apparatus. If desired, some modifying material such as a sensitizer may be introduced to the system simultaneously with the preparation of the silver halide in the operation.

Another type of operation in which the mixing apparatus in accordance with my invention is useful is in the preparation of barium sulfate in comminuted form. For instance, the bulk liquid may be an aqueous solution of sodium sulfate and an aqueous solution of barium chloride upon introduction thereto through the mixing apparatus in accordance with my invention will form barium sulfate in dispersed condition. This material is useful for use in the application of baryta coatings to paper employed in the photographic industry.

My invention is useful when the fluid to be introduced is a gas. For example, by using the device according to the invention finely divided air can be introduced into the midst of a fermenting mass to accelerate fermentation. The mixing apparatus described is especially desirable in any situation in which the introduction of a fluid in a well dispersed condition at the moment of its introduction into a bulk liquid mass is desirable.

In those cases where the mixer of my invention does not provide suflicient agitation to a mass particularly in large scale operations, it is desirable that one or more conventional mixing means such as a propellor agitator such as described and claimed in application Serial No.

459,004 of Leon D. Fessenden, now Patent No. 2,794,628, granted June 4, 1957, also be placed in the container in which the mixing is conducted. Any type of stirrer which provides good circulation of the bulk liquid in the container would be useful for assisting in the mixing operation with a rotating nozzle type mixer in accordance with my invention.

I claim:

1. A device for dispersing a small amount of fluid into a large body of liquid which comprises a rotating nozzle mixer of the revolving cone type having two closely facing equidiameter coaxial cones, the face of one cone being indented, that of the other being planar, said cones being attached to and rotated by an undivided hollow shaft having at least one opening from the interior of the shaft into the space between the cones, said shaft being connected to a means for rotating the shaft and in turn the cones, means being provided for feeding fluid into said shaft.

2. A device in accordance with claim 1 having means for adjusting the spacing of the cones.

3. A device in accordance with claim 1 in which the face of the indented cone is annularly grooved.

4. A device in accordance with claim 1 the cones of which are within a partial enclosure provided with baffle plates adapted to contribute to the radial flow of liquid in the area surrounding the cones.

5. A device in accordance with claim 1 the hollow shaft of which is provided (1) with a centrifugal trap and (2) with a feed pipe adapted to supply liquid to the interior of said shaft.

References Cited in the file of this patent UNITED STATES PATENTS 1,242,445 Ittner Oct. 9, 1917 1,771,369 Andersen July 22, 1930 2,203,673 Cornell June 11, 1940 2,273,835 Cornell Feb. 24, 1942 2,324,824 Cornell July 20, 1943 2,397,326 Payne et a1 Mar. 26, 1946 2,678,885 Porter May 18, 1954 2,743,914 Epprecht May 1, 1956 2,752,246 Weaver June 26, 1956 2,787,447 Crawford Apr. 2, 1957 FOREIGN PATENTS 70,842 Denmark Mar. 27, 1950 838,593 Germany May 12, 1952 

